view src/share/vm/oops/methodKlass.hpp @ 452:00b023ae2d78

6722113: CMS: Incorrect overflow handling during precleaning of Reference lists Summary: When we encounter marking stack overflow during precleaning of Reference lists, we were using the overflow list mechanism, which can cause problems on account of mutating the mark word of the header because of conflicts with mutator accesses and updates of that field. Instead we should use the usual mechanism for overflow handling in concurrent phases, namely dirtying of the card on which the overflowed object lies. Since precleaning effectively does a form of discovered list processing, albeit with discovery enabled, we needed to adjust some code to be correct in the face of interleaved processing and discovery. Reviewed-by: apetrusenko, jcoomes
author ysr
date Thu, 20 Nov 2008 12:27:41 -0800
parents a61af66fc99e
children 4e6abf09f540
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/*
 * Copyright 1997-2006 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

// a methodKlass is the klass of a methodOop

class methodKlass : public Klass {
  friend class VMStructs;
 private:
  juint    _alloc_size;        // allocation profiling support
 public:
  // Testing
  bool oop_is_method() const { return true; }

  // Allocation
  DEFINE_ALLOCATE_PERMANENT(methodKlass);
  methodOop allocate(constMethodHandle xconst, AccessFlags access_flags,
                     TRAPS);
  static klassOop create_klass(TRAPS);

  // Sizing
  int oop_size(oop obj) const;
  int klass_oop_size() const     { return object_size(); }

  // Casting from klassOop
  static methodKlass* cast(klassOop k) {
    assert(k->klass_part()->oop_is_method(), "cast to methodKlass");
    return (methodKlass*) k->klass_part();
  }

  // Sizing
  static int header_size()       { return oopDesc::header_size() + sizeof(methodKlass)/HeapWordSize; }
  int object_size() const        { return align_object_size(header_size()); }

  // Garbage collection
  void oop_follow_contents(oop obj);
  int  oop_adjust_pointers(oop obj);
  bool oop_is_parsable(oop obj) const;

  // Parallel Scavenge and Parallel Old
  PARALLEL_GC_DECLS

  // Allocation profiling support
  juint alloc_size() const              { return _alloc_size; }
  void set_alloc_size(juint n)          { _alloc_size = n; }

  // Iterators
  int oop_oop_iterate(oop obj, OopClosure* blk);
  int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr);

#ifndef PRODUCT
 public:
  // Printing
  void oop_print_on      (oop obj, outputStream* st);
  void oop_print_value_on(oop obj, outputStream* st);
#endif

 public:
  // Verify operations
  const char* internal_name() const;
  void oop_verify_on(oop obj, outputStream* st);
  bool oop_partially_loaded(oop obj) const;
  void oop_set_partially_loaded(oop obj);
};